Heat Sink, Heat Dissipation Apparatus, Heat Dissipation System, And Communications Device

ABSTRACT

One example heat sink includes a heat dissipation substrate, a connector, and a fastener. The heat dissipation substrate is configured to dissipate heat for a packaged chip located on a circuit board, and the heat dissipation substrate is located on a surface that is of the packaged chip and that is opposite to the circuit board. A first heat dissipation substrate and a second heat dissipation substrate of the heat dissipation substrate each have a heat conduction surface that conducts heat with a chip in the packaged chip. Different heat conduction surfaces correspond to different chips.

CROSS-REFERENCE TO RELATED DISCLOSURES

This application is a continuation of U.S. patent application Ser. No.16/298,443, filed on Mar. 11, 2019, which is a continuation ofInternational Application No. PCT/CN2017/100378, filed on Sep. 4, 2017,which claims priority to Chinese Patent Application No. 201610820551.1,filed on Sep. 12, 2016. All of the afore-mentioned patent applicationsare hereby incorporated by reference in their entireties.

TECHNICAL FIELD

This disclosure relates to heat dissipation technologies, and inparticular, to a heat sink, a heat dissipation apparatus, a heatdissipation system, and a communications device.

BACKGROUND

As science and technologies advance, to reduce sizes of electronicproducts, package sizes of chips used to construct electronic productsneed to be reduced. That is, a plurality of chips are packaged in a samepackage body, to effectively reduce a package size of chips, and reducesizes of electronic products. How to effectively dissipate heat for theplurality of chips is an existing problem that needs to be urgentlyresolved.

SUMMARY

Embodiments of this disclosure provide a heat sink, a heat dissipationapparatus, a heat dissipation system, and a communications device, toovercome a prior-art problem that heat of each chip in a packaged chipcannot be properly and effectively dissipated, and as a result, aservice life of a chip having a relatively low temperature is reduced,and a service life of an electronic product is reduced.

According to a first aspect of this disclosure, a heat sink is provided,including:

a heat dissipation substrate, a connector, and a fastener, where theheat dissipation substrate is configured to dissipate heat for apackaged chip located on a circuit board, and the heat dissipationsubstrate is located on a surface that is of the packaged chip and thatis opposite to the circuit board; and

the heat dissipation substrate includes a first heat dissipationsubstrate and a second heat dissipation substrate, the first heatdissipation substrate and the second heat dissipation substrate eachhave a heat conduction surface that conducts heat with a chip in thepackaged chip, different heat conduction surfaces correspond todifferent chips, a first end of the connector is fastened to the firstheat dissipation substrate, a second end of the connector suspends on anouter side of the second heat dissipation substrate, and the fastenerpresses against an outer side of the first heat dissipation substrate,to prevent the first heat dissipation substrate from moving far awayfrom the second heat dissipation substrate.

In this embodiment, different heat dissipation substrates of the heatsink may separately dissipate heat for different chips in the packagedchip, and the different heat dissipation substrates are connected byusing the connector. Therefore, neighboring heat dissipation substratescan conduct heat only by using the connector, and have a relatively slowheat conduction speed, thereby effectively obstructing heat conductionbetween the neighboring heat dissipation substrates. When temperaturesof chips below heat dissipation substrates are different, heat emittedby each chip does not transfer to another chip by using the heatdissipation substrate. To be specific, in a process of using the heatsink, heat emitted by a chip having a high temperature does not transferto a chip having a low temperature, thereby effectively increasing aservice life of a chip having a relatively low temperature, andincreasing a service life of an electronic product.

In some embodiments of the first aspect, the heat conduction surfaces ofthe first heat dissipation substrate and the second heat dissipationsubstrate are both in a same plane.

In this embodiment, because surfaces that are of chips in the packagedchip and that are away from the circuit board are all in the same plane,the heat conduction surfaces of the first heat dissipation substrate andthe second heat dissipation substrate are both in the same plane.Therefore, this can ensure that the heat conduction surfaces of the heatdissipation substrates all are in contact with each chip in the packagedchip, and avoid that the heat dissipation substrates are undesirably incontact with the packaged chip.

In some embodiments of the first aspect, the connector is of anelongated shape.

In some other embodiments of the first aspect, the connector issheet-shaped.

In the foregoing embodiment, when the connector is of an elongated shapeor sheet-shaped, the connector may be joined between the first heatdissipation substrate and the second heat dissipation substrate. Becausea cross-sectional area of the connector of an elongated shape or asheet-shaped connector is relatively small in a length direction, lessheat can be conducted per unit time based on a heat conduction law, thatis, a heat conduction speed is slow. In this way, because the lengthdirection of the connector is usually a heat transfer direction, thecross-sectional area of the connector in this direction is generallyless than a cross-sectional area of a connected part formed when thefirst heat dissipation substrate and the second heat dissipationsubstrate are directly connected. A first connection surface may bedefined as a surface that is on the first heat dissipation substrate andthat is opposite to the second heat dissipation substrate, and a secondconnection surface may be defined as a surface that is on the secondheat dissipation substrate and that is opposite to the first heatdissipation substrate. Generally, the cross-sectional area of theconnector in a heat conduction direction of the connector should be lessthan an overlapped area of the first connection surface and the secondconnection surface. It should be noted that the shape of the connectoris not limited to an elongated shape or a sheet shape, and mayalternatively be another structural form having a relatively smallcross-sectional area.

In some embodiments of the first aspect, an arrangement groove isprovided at a position that is on the second heat dissipation substrateand that corresponds to the connector, and the arrangement groove isused to avoid the connector.

In this embodiment, because the second end of the connector suspends onthe outer side of the second heat dissipation substrate, to avoidinterference between the connector and the second heat dissipationsubstrate and further stably fasten the connector, the second heatdissipation substrate is provided with the arrangement groove. A sizeand a depth of the arrangement groove both match the connector, so thatthe second end of the connector can be placed in the arrangement grooveto avoid interference between the connector and the second heatdissipation substrate. In addition, a shape of the arrangement groovecan fasten and position the connector in a direction parallel to theheat dissipation substrate.

In some embodiments of the first aspect, there are at least twoconnectors. When there are a plurality of connectors, the plurality ofconnectors may be symmetrically disposed on two sides of the first heatdissipation substrate, to strengthen stability of connection between thefirst heat dissipation substrate and the second heat dissipationsubstrate.

In some embodiments of the first aspect, the connector is provided witha first through hole, and a second through hole is provided at aposition that is on the second heat dissipation substrate and thatcorresponds to the first through hole. In this case, the fastenerfurther includes a fastening screw, the fastening screw passes throughthe first through hole and the second through hole, the first heatdissipation substrate is located between a head portion of the fasteningscrew and the second heat dissipation substrate, and a tail portion ofthe fastening screw is securely connected to the second heat dissipationsubstrate, to connect the first heat dissipation substrate to the secondheat dissipation substrate.

In this embodiment, because the fastening screw used to connect theconnector to the second heat dissipation substrate implements fasteningand connection by relying on a common threaded connection, a connectionis relatively reliable. In addition, in a threaded connection, a throughhole of the connector or the second heat dissipation substrate isgenerally in point contact with or is in line contact with a thread ofthe fastening screw, and a contact surface is relatively small.Therefore, this can further reduce a heat conduction speed of theconnector and the second heat dissipation substrate, and ensure heatinsulation performance of the first heat dissipation substrate and thesecond heat dissipation substrate.

Further, based on the foregoing embodiment, the fastener furtherincludes an elastic member, and two ends of the elastic memberrespectively press between the head portion of the fastening screw andthe first heat dissipation substrate, so that the first heat dissipationsubstrate is in contact with the packaged chip under an elastic force ofthe elastic member.

In this embodiment, the elastic member of the fastener can press againstboth the fastening screw and the first heat dissipation substrate.Because the fastening screw and the second heat dissipation substrateare securely connected, and maintain fixed relative positions, under theforce of the elastic member, the first heat dissipation substrate ispressed to the second heat dissipation substrate under the force of theelastic member, to generate a movable effect. This can prevent the firstheat dissipation substrate from moving far away from the second heatdissipation substrate, and the first heat dissipation substrate and thesecond heat dissipation substrate can keep being in contact with thepackaged chip as much as possible. To be specific, the heat conductionsurfaces of the first heat dissipation substrate and the second heatdissipation substrate are coplanar.

In some embodiments of the first aspect, the second heat dissipationsubstrate is connected to the second end of the connector by using heatinsulation glue.

In this embodiment, the heat insulation glue is disposed between thesecond end of the connector and the second heat dissipation substrate,to obstruct heat transfer between the connector and the second heatdissipation substrate, and further avoid heat transfer between the firstheat dissipation substrate and the second heat dissipation substrate.

In addition, in this embodiment, the second end of the connector may besoldered to the second heat dissipation substrate by using solderingtin, to implement fastening of the second end of the connector and thesecond heat dissipation substrate.

In some embodiments of the first aspect, the fastener includes: a firstpositioning stud and a second positioning stud; and

a bottom end of the first positioning stud is connected to the secondheat dissipation substrate, an axial direction of the first positioningstud is perpendicular to a plane in which the second heat dissipationsubstrate lies, the second positioning stud can be screwed into a topend of the first positioning stud, and the second end of the connectoris fastened at a position at which the first positioning stud is screwedinto the second positioning stud.

In this embodiment, a double-layer stud structure is used, a contactsurface of the connector and the positioning stud is generallyrelatively small, and there is usually a gap. Therefore, a heat transferspeed and heat transfer efficiency of the connector and the positioningstud are both relatively low, and heat transfer to different heatdissipation substrates through the connector can be relatively desirablyavoided.

In some embodiments of the first aspect, a perpendicular distancebetween the second end of the connector and the plane in which thesecond heat dissipation substrate lies is different from a perpendiculardistance between the first end of the connector and the plane in whichthe second heat dissipation substrate lies.

In this embodiment, because the connector may be connected to the secondheat dissipation substrate by using a structure such as a double-layerpositioning stud, to avoid another connection structure, the second endand the first end of the connector may be generally located at positionsaway from the plane in which the second heat dissipation substrate liesby different distances, so that the second end of the connector avoidsthe connection structure for fastening.

In some embodiments of the first aspect, the first end of the connectoris connected to the second end of the connector by using a bendingsegment.

In some embodiments of the first aspect, the second heat dissipationsubstrate is provided with a notch, at least a part of the first heatdissipation substrate is located in the notch, and an outer-edge shapeof the part of the first heat dissipation substrate that is located inthe notch matches a shape of the notch.

In this embodiment, because the second heat dissipation substrate isprovided with the notch, at least the part of the first heat dissipationsubstrate can enter the notch, so that the position of the heatdissipation substrate can better correspond to positions of differentchips in the packaged chip, and an overall area and an overall size ofthe heat dissipation substrate are reduced.

In some embodiments of the first aspect, the first heat dissipationsubstrate is completely located in the notch.

In some embodiments of the first aspect, the second heat dissipationsubstrate encloses the outer side of the first heat dissipationsubstrate and forms a closed shape.

In some embodiments of the first aspect, the heat sink further includes:a first heat dissipation fin group used to dissipate heat for the firstheat dissipation substrate and a second heat dissipation fin group usedto dissipate heat for the second heat dissipation substrate, the firstheat dissipation fin group is located on a surface that is of the firstheat dissipation substrate and that is opposite to the heat conductionsurface, the second heat dissipation fin group is located on a surfacethat is of the second heat dissipation substrate and that is opposite tothe heat conduction surface, a cold air path is formed inside the secondheat dissipation fin group, the second heat dissipation fin group isprovided with second heat dissipation fins, the second heat dissipationfin is located on two sides of the cold air path, and the first heatdissipation fin group is located in the cold air path or on an extensionline of the cold air path.

In this embodiment, each heat dissipation substrate of the heat sink isfurther connected to a heat dissipation fin group that dissipates heatfor the heat dissipation substrate. The second heat dissipation fingroup on the second heat dissipation substrate is provided with a coldair path passing through the entire second heat dissipation fin group,so that an external cooling airflow can be blown to the first heatdissipation fin group through the cold air path, and the first heatdissipation fin group and the second heat dissipation fin group bothhave relatively high heat dissipation efficiency.

In some implementations of the first aspect, third heat dissipation finsare further disposed in the cold air path, and a height of the thirdheat dissipation fin is less than a height of the second heatdissipation fin.

In this embodiment, the third heat dissipation fin can assist heatdissipation. In addition, because the height of the third heatdissipation fin is relatively low, it can still be ensured that coolingairflow can pass through the cold air path.

In some implementations of the first aspect, fourth heat dissipationfins are further disposed in the cold air path, and a density of thefourth heat dissipation fins is less than a density of the second heatdissipation fins.

In this embodiment, the fourth heat dissipation fin in the cold air pathcan assist heat dissipation of the second heat dissipation substrate. Inaddition, a density of the fourth heat dissipation fins is less than adensity of the second heat dissipation fins, and it can still be ensuredthat cooling airflow can pass through the cold air path.

In some implementations of the first aspect, the heat sink furtherincludes: a fifth heat dissipation fin group used to dissipate heat forthe first heat dissipation substrate and a sixth heat dissipation fingroup used to dissipate heat for the second heat dissipation substrate,and the fifth heat dissipation fin group and the sixth heat dissipationfin group are stacked on a surface that is of the heat dissipationsubstrate and that is opposite to the heat conduction surface; and

the fifth heat dissipation fin group is located between the sixth heatdissipation fin group and the heat dissipation substrate, or the sixthheat dissipation fin group is located between the fifth heat dissipationfin group and the heat dissipation substrate.

In this embodiment, the heat dissipation fin groups respectively used todissipate heat for the two heat dissipation substrates are stacked onthe heat dissipation substrates from top to bottom, so that when an areaof the heat dissipation substrate is relatively small and it isdifficult to form an effective cold air path, height space above theheat dissipation substrate can be used to dispose the heat dissipationfin group, to ensure heat dissipation efficiency of the heat dissipationsubstrate.

In some implementations of the first aspect, a semiconductor coolingchip is disposed on the heat conduction surface of the at least one heatdissipation substrate, and the semiconductor cooling chip is in contactwith a corresponding chip in the packaged chip.

In this embodiment, the semiconductor cooling chip is disposed on theheat conduction surface of the heat dissipation substrate, so that aheat transfer speed of the heat conduction surface may be increased, andheat dissipation efficiency of the heat sink may be improved by using afeature of electron mobility of a semiconductor. In addition,alternatively, a heat conduction speed of the heat conduction surface ofthe heat dissipation substrate may be increased by using a cooling chipof another principle.

In some implementations of the first aspect, a heat conduction rate of amaterial that the connector is made of is less than a heat conductionrate of a material that the heat dissipation substrate is made of.

In this embodiment, because the heat conduction rate of the connector isless than the heat conduction rate of the heat dissipation substrate, aheat conduction speed of the connector is further reduced, and a heatinsulation level of different heat dissipation substrates is improved.

According to a second aspect of this disclosure, a heat sink isprovided, including a heat dissipation substrate, where the heatdissipation substrate is configured to dissipate heat for a packagedchip located on a circuit board, and the heat dissipation substrate islocated on a surface that is of the packaged chip and that is oppositeto the circuit board; and

the heat dissipation substrate includes a first heat dissipationsubstrate and a second heat dissipation substrate, the first heatdissipation substrate and the second heat dissipation substrate eachhave a heat conduction surface that conducts heat with a chip in thepackaged chip, different heat conduction surfaces correspond todifferent chips, the first heat dissipation substrate is connected tothe second heat dissipation substrate by using a connector, a heatconduction coefficient of the connector is less than a heat conductioncoefficient of the first heat dissipation sub-substrate, and the heatconduction coefficient of the connector is less than a heat conductioncoefficient of the second heat dissipation substrate.

In this embodiment, the plurality of heat dissipation substrates thatdissipate heat for different chips are connected by using the connectorhaving a relatively low heat conduction coefficient. Because less heatis conducted between the heat dissipation substrates, when temperaturesof chips below heat dissipation sub-substrates are different, heatemitted by each chip does not transfer to another chip by using the heatdissipation substrate. To be specific, in a process of using the heatsink, heat emitted by a chip having a high temperature does not transferto a chip having a low temperature, thereby effectively increasing aservice life of a chip having a relatively low temperature, andincreasing a service life of an electronic product.

In some implementations of the second aspect, the heat conductionsurfaces of the first heat dissipation substrate and the second heatdissipation substrate are both in a same plane.

In this embodiment, because surfaces that are of chips in the packagedchip and that are away from the circuit board are all in the same plane,the heat conduction surfaces of the first heat dissipation substrate andthe second heat dissipation substrate are both in the same plane.Therefore, this can ensure that the heat conduction surfaces of the heatdissipation substrates all are in contact with each chip in the packagedchip, and avoid that the heat dissipation substrates are undesirably incontact with the packaged chip.

In some implementations of the second aspect, a material that theconnector is made of is a heat-insulation material.

In this embodiment, the connector is made of the heat-insulationmaterial, and a heat transfer process of the neighboring first heatdissipation substrates and second heat dissipation substrate can bealleviated to the maximum extent, so that an approximate heat insulationstate exists between the different heat dissipation substrates, heatemitted by a chip having a high temperature is prevented fromtransferring to a chip having a low temperature, and a service life ofthe chip is increased.

In some implementations of the second aspect, an arrangement groove isprovided at a position that is on the second heat dissipation substrateand that corresponds to the connector, and the arrangement groove isused to avoid the connector.

In this embodiment, because the second end of the connector suspends onthe outer side of the second heat dissipation substrate, to avoidinterference between the connector and the second heat dissipationsubstrate and further stably fasten the connector, the second heatdissipation substrate is provided with the arrangement groove. A sizeand a depth of the arrangement groove both match the connector, so thatthe second end of the connector can be placed in the arrangement grooveto avoid interference between the connector and the second heatdissipation substrate. In addition, a shape of the arrangement groovecan fasten and position the connector in a direction parallel to theheat dissipation substrate.

In some embodiments of the second aspect, there are at least twoconnectors. When there are a plurality of connectors, the plurality ofconnectors may be symmetrically disposed on two sides of the first heatdissipation substrate, to strengthen stability of connection between thefirst heat dissipation substrate and the second heat dissipationsubstrate.

In some embodiments of the second aspect, the connector is provided witha first through hole, and a second through hole is provided at aposition that is on the second heat dissipation substrate and thatcorresponds to the first through hole. In this case, the fastenerfurther includes a fastening screw, the fastening screw passes throughthe first through hole and the second through hole, the first heatdissipation substrate is located between a head portion of the fasteningscrew and the second heat dissipation substrate, and a tail portion ofthe fastening screw is securely connected to the second heat dissipationsubstrate, to connect the first heat dissipation substrate to the secondheat dissipation substrate.

In this embodiment, because the fastening screw used to connect theconnector to the second heat dissipation substrate implements fasteningand connection by relying on a common threaded connection, a connectionis relatively reliable. In addition, in a threaded connection, a throughhole of the connector or the second heat dissipation substrate isgenerally in point contact with or is in line contact with a thread ofthe fastening screw, and a contact surface is relatively small.Therefore, this can further reduce a heat conduction speed of theconnector and the second heat dissipation substrate, and ensure heatinsulation performance of the first heat dissipation substrate and thesecond heat dissipation substrate.

Further, based on the foregoing embodiment, the fastener furtherincludes an elastic member, and two ends of the elastic memberrespectively press between the head portion of the fastening screw andthe first heat dissipation substrate, so that the first heat dissipationsubstrate is in contact with the packaged chip under an elastic force ofthe elastic member.

In this embodiment, the elastic member of the fastener can press againstboth the fastening screw and the first heat dissipation substrate.Because the fastening screw and the second heat dissipation substrateare securely connected, and maintain fixed relative positions, under theforce of the elastic member, the first heat dissipation substrate ispressed to the second heat dissipation substrate under the force of theelastic member, to generate a floating effect. This can prevent thefirst heat dissipation substrate from moving far away from the secondheat dissipation substrate, and the first heat dissipation substrate andthe second heat dissipation substrate can keep being in contact with thepackaged chip as much as possible. To be specific, the heat conductionsurfaces of the first heat dissipation substrate and the second heatdissipation substrate are coplanar.

In some embodiments of the second aspect, the second heat dissipationsubstrate is connected to the connector by using heat insulation glue.

In this embodiment, the heat insulation glue is disposed between theconnector and the second heat dissipation substrate, to obstruct heattransfer between the connector and the second heat dissipationsubstrate, and further avoid heat transfer between the first heatdissipation substrate and the second heat dissipation substrate.

In addition, in this embodiment, the connector may be soldered to thesecond heat dissipation substrate by using soldering tin, to implementfastening of the connector and the second heat dissipation substrate.

In some embodiments of the second aspect, the heat sink includes: afirst positioning stud and a second positioning stud; and

a bottom end of the first positioning stud is connected to the secondheat dissipation substrate, an axial direction of the first positioningstud is perpendicular to a plane in which the second heat dissipationsubstrate lies, the second positioning stud can be screwed into a topend of the first positioning stud, the first end of the connector isfastened to the first heat dissipation substrate, and the second end ofthe connector is fastened at a position at which the first positioningstud is screwed into the second positioning stud.

In this embodiment, a double-layer stud structure is used, the secondend of the connector is fastened between the first positioning stud andthe second positioning stud, and the first positioning stud is fastenedon the second heat dissipation substrate. In this way, a connectionbetween the connector and the second heat dissipation substrate isindirectly implemented by using the stud. A contact surface of theconnector and the positioning stud is generally relatively small, andthere is usually a gap. Therefore, a heat transfer speed and heattransfer efficiency of the connector and the positioning stud are bothrelatively low, and heat transfer to different heat dissipationsubstrates through the connector can be relatively desirably avoided.

In some embodiments of the second aspect, a perpendicular distancebetween the second end of the connector and the plane in which thesecond heat dissipation substrate lies is different from a perpendiculardistance between the first end of the connector and the plane in whichthe second heat dissipation substrate lies.

In this embodiment, because the connector may be connected to the secondheat dissipation substrate by using a structure such as a double-layerpositioning stud, to avoid another connection structure, the second endand the first end of the connector may be generally located at positionsaway from the plane in which the second heat dissipation substrate liesby different distances, so that the second end of the connector avoidsthe connection structure for fastening.

In some embodiments of the second aspect, the first end of the connectoris connected to the second end of the connector by using a bendingsegment.

In some embodiments of the second aspect, the second heat dissipationsubstrate is provided with a notch, at least a part of the first heatdissipation substrate is located in the notch, and an outer-edge shapeof the part of the first heat dissipation substrate that is located inthe notch matches a shape of the notch.

In this embodiment, because the second heat dissipation substrate isprovided with the notch, at least the part of the first heat dissipationsubstrate can enter the notch, so that the position of the heatdissipation substrate can better correspond to positions of differentchips in the packaged chip, and an overall area and an overall size ofthe heat dissipation substrate are reduced.

In some embodiments of the second aspect, the first heat dissipationsubstrate is completely located in the notch.

In some embodiments of the second aspect, the second heat dissipationsubstrate encloses the outer side of the first heat dissipationsubstrate and forms a closed shape.

In some embodiments of the second aspect, the heat sink furtherincludes: a first heat dissipation fin group used to dissipate heat forthe first heat dissipation substrate and a second heat dissipation fingroup used to dissipate heat for the second heat dissipation substrate,the first heat dissipation fin group is located on a surface that is ofthe first heat dissipation substrate and that is opposite to the heatconduction surface, the second heat dissipation fin group is located ona surface that is of the second heat dissipation substrate and that isopposite to the heat conduction surface, a cold air path is formedinside the second heat dissipation fin group, the second heatdissipation fin group is provided with second heat dissipation fins, thesecond heat dissipation fin is located on two sides of the cold airpath, and the first heat dissipation fin group is located in the coldair path or on an extension line of the cold air path.

In this embodiment, each heat dissipation substrate of the heat sink isfurther connected to a heat dissipation fin group that dissipates heatfor the heat dissipation substrate. The second heat dissipation fingroup on the second heat dissipation substrate is provided with a coldair path passing through the entire second heat dissipation fin group,so that an external cooling airflow can be blown to the first heatdissipation fin group through the cold air path, and the first heatdissipation fin group and the second heat dissipation fin group bothhave relatively high heat dissipation efficiency.

In some implementations of the second aspect, third heat dissipationfins are further disposed in the cold air path, and a height of thethird heat dissipation fin is less than a height of the second heatdissipation fin.

In this embodiment, because the cold air path has the third heatdissipation fin having a relatively low height, the third heatdissipation fin can assist heat dissipation, and heat dissipationefficiency on the second heat dissipation substrate is ensured. Inaddition, because the height of the third heat dissipation fin isrelatively low, it can still be ensured that cooling airflow can passthrough the cold air path.

In some implementations of the second aspect, fourth heat dissipationfins are further disposed in the cold air path, and a density of thefourth heat dissipation fins is less than a density of the second heatdissipation fins.

In this embodiment, the fourth heat dissipation fin in the cold air pathcan assist heat dissipation of the second heat dissipation substrate. Inaddition, a density of the fourth heat dissipation fins is less than adensity of the second heat dissipation fins, and it can still be ensuredthat cooling airflow can pass through the cold air path.

In some implementations of the second aspect, the heat sink furtherincludes: a fifth heat dissipation fin group used to dissipate heat forthe first heat dissipation substrate and a sixth heat dissipation fingroup used to dissipate heat for the second heat dissipation substrate,and the fifth heat dissipation fin group and the sixth heat dissipationfin group are stacked on a surface that is of the heat dissipationsubstrate and that is opposite to the heat conduction surface; and

the fifth heat dissipation fin group is located between the sixth heatdissipation fin group and the heat dissipation substrate, or the sixthheat dissipation fin group is located between the fifth heat dissipationfin group and the heat dissipation substrate.

In this embodiment, the heat dissipation fin groups respectively used todissipate heat for the two heat dissipation substrates are stacked onthe heat dissipation substrates from top to bottom, so that when an areaof the heat dissipation substrate is relatively small and it isdifficult to form an effective cold air path, height space above theheat dissipation substrate can be used to dispose the heat dissipationfin group, to ensure heat dissipation efficiency of the heat dissipationsubstrate.

In some implementations of the second aspect, a semiconductor coolingchip is disposed on the heat conduction surface of the at least one heatdissipation substrate, and the semiconductor cooling chip is in contactwith a corresponding chip in the packaged chip.

In this embodiment, the semiconductor cooling chip is disposed on theheat conduction surface of the heat dissipation substrate, so that aheat transfer speed of the heat conduction surface may be increased, andheat dissipation efficiency of the heat sink may be improved by using afeature of electron mobility of a semiconductor. In addition,alternatively, a heat conduction speed of the heat conduction surface ofthe heat dissipation substrate may be increased by using a cooling chipof another principle.

According to a third aspect of this disclosure, a heat dissipationapparatus is provided, including at least two heat sinks according toany one of the first aspect or the second aspect and at least one heatpipe, where

each heat sink corresponds to a packaged chip; and

two ends of the heat pipe are respectively connected to heat dissipationsubstrates of different heat sinks, to transfer heat of a heat sinkcorresponding to a packaged chip in a heat emitting state to a heat sinkcorresponding to a packaged chip that does not emit heat.

In this embodiment, different heat sinks are connected by using the atleast one heat pipe, and heat of a packaged chip that is in a workingand heat emitting state may be transferred, by using the connectionbetween the heat sink and the heat pipe, to a heat sink corresponding toa packaged chip that does not work or does not emit heat, to moreeffectively facilitate temperature reduction of different packagedchips.

According to a fourth aspect of this disclosure, a heat dissipationsystem is provided, including: at least one heat sink according to anyone of the first aspect or the second aspect and at least one packagedchip, where each heat sink corresponds to a packaged chip; and

the heat sink is used to dissipate heat for the packaged chip.

In this embodiment, each packaged chip is provided with a heat sink,different heat dissipation substrates of the heat sink may dissipateheat for different chips in the packaged chip, so that when heat of thechips in the packaged chip is different, heat of each chip isindependently and effectively dissipated, to ensure normal working and aservice life of each chip in the packaged chip.

According to a fifth aspect of this disclosure, a communications deviceis provided, including at least one heat sink according to any one ofthe first aspect or the second aspect, at least one packaged chip, andat least one circuit board, where

each circuit board is provided with at least one packaged chip; and

each heat sink corresponds to a packaged chip, and the heat sink is usedto dissipate heat for the packaged chip.

In this embodiment, a packaged chip on the circuit board in thecommunications device is provided with a heat sink, different heatdissipation substrates of the heat sink may dissipate heat for differentchips in the packaged chip, so that when heat of the chips in thepackaged chip is different, heat of each chip is independently andeffectively dissipated, to ensure normal working and a service life ofeach chip in the packaged chip.

This disclosure provides the heat sink, the heat dissipation apparatus,the heat dissipation system, and the communications device. The heatsink includes: the heat dissipation substrate, the connector, and thefastener, where the heat dissipation substrate is configured todissipate heat for a packaged chip located on the circuit board, and theheat dissipation substrate is located on the surface that is of thepackaged chip and that is opposite to the circuit board; and the heatdissipation substrate includes the first heat dissipation substrate andthe second heat dissipation substrate, the first heat dissipationsubstrate and the second heat dissipation substrate each have the heatconduction surface that conducts heat with a chip in the packaged chip,different heat conduction surfaces correspond to different chips, thefirst end of the connector is fastened to the first heat dissipationsubstrate, the second end of the connector suspends on the outer side ofthe second heat dissipation substrate, and the fastener presses againstthe outer side of the first heat dissipation substrate, to prevent thefirst heat dissipation substrate from moving far away from the secondheat dissipation substrate. When temperatures of chips below heatdissipation substrates are different, heat emitted by each chip does nottransfer to another chip by using the heat dissipation substrate. To bespecific, in a process of using the heat sink, heat emitted by a chiphaving a high temperature does not transfer to a chip having a lowtemperature, thereby effectively increasing a service life of a chiphaving a relatively low temperature, and increasing a service life of anelectronic product.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an outline diagram of a heat sink according to Embodiment 1 ofthis disclosure;

FIG. 2 is a schematic structural diagram of a heat sink according toEmbodiment 1 of this disclosure;

FIG. 3 is a specific schematic structural diagram of a first heatdissipation substrate of the heat sink shown in FIG. 2;

FIG. 4 is a specific schematic structural diagram of a second heatdissipation substrate of the heat sink shown in FIG. 2;

FIG. 5 is a schematic diagram of connection and fastening of a firstheat dissipation substrate and a second heat dissipation substrateaccording to Embodiment 1 of this disclosure;

FIG. 6 is a diagram 1 of relative locations of a first heat dissipationsubstrate and a second heat dissipation substrate according toEmbodiment 1 of this disclosure;

FIG. 7 is a diagram 2 of relative locations of a first heat dissipationsubstrate and a second heat dissipation substrate according toEmbodiment 1 of this disclosure;

FIG. 8 is a diagram 3 of relative locations of a first heat dissipationsubstrate and a second heat dissipation substrate according toEmbodiment 1 of this disclosure;

FIG. 9 is a diagram 4 of relative locations of a first heat dissipationsub-substrate and a second heat dissipation sub-substrate according toEmbodiment 1 of this disclosure;

FIG. 10 is a schematic structural diagram 1 of a heat dissipation fingroup according to Embodiment 1 of this disclosure;

FIG. 11 is a schematic structural diagram 2 of a heat dissipation fingroup according to Embodiment 1 of this disclosure;

FIG. 12 is a schematic structural diagram 3 of a heat dissipation fingroup according to Embodiment 1 of this disclosure;

FIG. 13 is a schematic structural diagram 4 of a heat dissipation fingroup according to Embodiment 1 of this disclosure;

FIG. 14 is a schematic structural diagram of a heat sink according toEmbodiment 2 of this disclosure;

FIG. 15 is another schematic structural diagram of a heat sink accordingto Embodiment 2 of this disclosure;

FIG. 16 is a schematic structural diagram of a heat sink according toEmbodiment 3 of this disclosure;

FIG. 17 is a schematic structural diagram of a heat sink according toEmbodiment 4 of this disclosure;

FIG. 18 is a specific schematic structural diagram of a heat dissipationapparatus according to Embodiment 5 of this disclosure;

FIG. 19 is a specific schematic structural diagram of a heat dissipationsystem according to Embodiment 6 of this disclosure; and

FIG. 20 is a specific schematic structural diagram of a communicationsdevice according to Embodiment 7 of this disclosure.

DESCRIPTION OF EMBODIMENTS

A chip may include various electronic circuit components, and may beused to construct an electronic product, for example, a computer or amobile terminal.

As science and technologies advance, light weights and small sizesalready become development trends of electronic products. Therefore, asize of chip package in electronic products also should be reduced. Amulti-chip package body technology enabling chips having differentfunctions to be packaged in a same package body conforms to thedevelopment trends of electronic products because a high capacity and amulti-function operation are implemented in a single packaged product.For example, a system in package (SIP) technology can enable a pluralityof chips having different functions to be disposed on a same substrate,thereby effectively packaging the plurality of chips into a package bodyhaving a small size. For example, a microprocessor, a memory (forexample, an erasable programmable read-only memory (EPROM) and a dynamicrandom access memory (DRAM), a field-programmable gate array (FPGA), aresistor, a capacitor, and an inductor may be combined in a package bodyaccommodating up to four or five bare dies.

In development towards electronic products having light weights andsmall sizes, working reliability of devices in electronic products isalso a problem that needs to be paid attention to.

Because working temperatures of chips are different during normalworking, if neighboring chips in the packaged chip (a plurality of chipsare packaged in one package body) obtained by system in package transferheat, and to be specific, heat emitted by a chip having a relativelyhigh temperature transfers to a chip having a relatively lowtemperature, a temperature of the chip having the relatively lowtemperature is higher than a temperature of the chip during normalworking. As a result, a service life of the chip having the relativelylow temperature is reduced, and a service life of an electronic productis reduced.

A heat dissipation apparatus in the prior art includes a heatdissipation substrate and a heat dissipation fin provided on the heatdissipation substrate. During use, the heat dissipation apparatus isfastened above a package body of chips, so that the heat dissipationsubstrate of the heat dissipation apparatus is in contact with a surfaceof the package body of the chips, heat emitted by the chips transfers tothe heat dissipation fin, and the heat dissipation fin finallydissipates the heat. However, heat emitted by each chip in the samepackage body cannot be effectively dissipated simultaneously, and theheat dissipation substrate transfers heat emitted by a chip having arelatively high temperature to a chip having a relatively lowtemperature. As a result, a service life of a chip having a relativelylow temperature is reduced, and a service life of an electronic productis reduced.

In this disclosure, a heat dissipation substrate of a heat dissipationapparatus is divided into different heat dissipation sub-substrates,each sub-substrate corresponds to one chip in a packaged chip and isconfigured to dissipate heat for the chip, and sub-substrates do notconduct heat, so that heat generated by a chip having a relatively hightemperature does not transfer to a chip having a relatively lowtemperature. Therefore, a service life of a chip having a relatively lowtemperature is effectively increased, and a service life of anelectronic product is increased.

This disclosure is applied to a device such as a packaged chip obtainedby packaging a plurality of different chips into a same package body.

Specific embodiments are used below to describe in detail the technicalsolutions of this disclosure. The following several specific embodimentsmay be combined with each other, and a same or similar concept orprocess may not be described repeatedly in some embodiments.

FIG. 1 is an outline diagram of a heat sink according to Embodiment 1 ofthis disclosure. FIG. 2 is a schematic structural diagram of a heat sinkaccording to Embodiment 1 of this disclosure. FIG. 3 is a specificschematic structural diagram of a first heat dissipation substrate ofthe heat sink shown in FIG. 2. FIG. 4 is a specific schematic structuraldiagram of a second heat dissipation substrate of the heat sink shown inFIG. 2. As shown in FIG. 1 to FIG. 4, the heat sink in the embodimentsmay include a heat dissipation substrate 11, a connector 22, and afastener 33, where

the heat dissipation substrate 11 is used to dissipate heat for apackaged chip located on a circuit board, and the heat dissipationsubstrate 11 is located on a surface that is of the packaged chip andthat is opposite to the circuit board; and

the heat dissipation substrate 11 is usually made of a material such asaluminum and copper having relatively desirable heat conductivity, andthe heat dissipation substrate includes a first heat dissipationsubstrate 111 and a second heat dissipation substrate 112, the firstheat dissipation substrate 111 and the second heat dissipation substrate112 each have a heat conduction surface that conducts heat with a chipin the packaged chip, different heat conduction surfaces correspond todifferent chips, a first end of the connector 22 is fastened to thefirst heat dissipation substrate 111, a second end of the connector 22suspends on an outer side of the second heat dissipation substrate 112,and the fastener 33 presses against an outer side of the first heatdissipation substrate 111, to prevent the first heat dissipationsubstrate 111 from moving far away from the second heat dissipationsubstrate 112.

That a surface of the heat dissipation substrate is in contact with acorresponding chip in the packaged chip may be: each heat dissipationsubstrate corresponds to one chip in the packaged chip or may correspondto a plurality of chips in the packaged chip. In an implementablemanner, when each heat dissipation substrate corresponds to a pluralityof chips in the packaged chip, emitted heat and heat dissipationrequirements of the plurality of chips corresponding to each heatdissipation substrate are similar or the same.

In an implementable manner of this disclosure, the heat conductionsurfaces of the first heat dissipation substrate 111 and the second heatdissipation substrate 112 are both in a same plane. Because surfacesthat are of chips in the packaged chip and that are away from thecircuit board are all in the same plane, the heat conduction surfaces ofthe first heat dissipation substrate 111 and the second heat dissipationsubstrate 112 are both in the same plane. Therefore, this can ensurethat the heat conduction surfaces of the heat dissipation substrates 11all are in contact with each chip in the packaged chip, and avoid thatthe heat dissipation substrates 11 are undesirably in contact with thepackaged chip and a single heat dissipation substrate is not in contactwith a packaged chip.

In an implementable manner of this disclosure, the connector 22 is of anelongated shape. When the connector 22 is of an elongated shape, theconnector 22 may be joined between the first heat dissipation substrate111 and the second heat dissipation substrate 112. Because across-sectional area of a connector 22 of an elongated shape isrelatively small in a length direction, less heat can be conducted perunit time based on a heat conduction law, that is, a heat conductionspeed is slow. In this way, because the length direction of theconnector 22 is usually a heat transfer direction, the cross-sectionalarea of the connector 22 in this direction is generally less than across-sectional area of a connected part formed when the first heatdissipation substrate 111 and the second heat dissipation substrate 112are directly connected. A first connection surface may be defined as asurface that is on the first heat dissipation substrate 111 and that isopposite to the second heat dissipation substrate 112, and a secondconnection surface may be defined as a surface that is on the secondheat dissipation substrate 112 and that is opposite to the first heatdissipation substrate 111. Generally, the cross-sectional area of theconnector 22 in a heat conduction direction of the connector should beless than an overlapped area of the first connection surface and thesecond connection surface.

In another implementable manner of this disclosure, the connector 22 issheet-shaped. The sheet-shaped connector 22 also has a relatively smallcross-sectional area, and can effectively reduce a heat conduction speedof the connector 22, thereby obstructing a process of transferring heatbetween different heat dissipation substrates. Details are not describedherein again. In addition, the sheet-shaped connector 22 may have arelatively large width while having a relatively small cross-sectionalarea, to facilitate a connection to a fastening structure such as thefastener 33.

It should be noted that the shape of the connector is not limited to anelongated shape or a sheet shape, and may alternatively be anotherstructural form such as a hollow structure having a relatively smallcross-sectional area.

In an implementable manner of this disclosure, an arrangement groove1121 is provided at a position that is on the second heat dissipationsubstrate 112 and that corresponds to the connector 22, and thearrangement groove 1121 is used to avoid the connector 22.

Because the second end of the connector 22 suspends on the outer side ofthe second heat dissipation substrate 112 when the first heatdissipation substrate 112 is connected to the second heat dissipationsubstrate 111, if the connector 22 is directly connected to the secondheat dissipation substrate 112, a structure of the second heatdissipation substrate 112 may be interfered. FIG. 5 is a schematicdiagram of connection and fastening of a first heat dissipationsubstrate and a second heat dissipation substrate according toEmbodiment 1 of this disclosure. As shown in FIG. 5, to avoidinterference between the connector 22 and the second heat dissipationsubstrate 112 while reducing a distance between neighboring heatdissipation substrates as much as possible, the second heat dissipationsubstrate 112 needs to be provided with the arrangement groove 1121. Asize and a depth of the arrangement groove 1121 both match the connector22, so that the second end of the connector 22 can be placed in thearrangement groove 1121 to avoid interference between the connector 22and the second heat dissipation substrate 112. In addition, a shape ofthe arrangement groove 1121 can fasten and position the connector in adirection parallel to the heat dissipation substrate.

In an implementable manner of this disclosure, there are at least twoconnectors 22. When there are two or more connectors 22, the pluralityof connectors may be symmetrically disposed on two sides of the firstheat dissipation substrate, to strengthen stability of connectionbetween the first heat dissipation substrate 111 and the second heatdissipation substrate 112. In this embodiment, four connectors 22 arespecifically disposed, and the four connectors are separately connectedon two sides of the first heat dissipation substrate 111. This disposingmanner can effectively ensure fastening of the second heat dissipationsubstrate 112 and the first heat dissipation substrate 111.

To implement fastening of the connector 22 and the second heatdissipation substrate 112 and avoid disconnection of the first heatdissipation substrate 111 from the second heat dissipation substrate112, the fastener 33 may have a plurality of different forms. In animplementable manner of this disclosure, the connector 22 is providedwith a first through hole, and a second through hole is provided at aposition that is on the second heat dissipation substrate 112 and thatcorresponds to the first through hole. In this case, the fastener 33further includes a fastening screw 331, the fastening screw 331 passesthrough the first through hole and the second through hole, the firstheat dissipation substrate 111 is located between a head portion of thefastening screw 331 and the second heat dissipation substrate 112, and atail portion of the fastening screw 331 is securely connected to thesecond heat dissipation substrate 112, to connect the first heatdissipation substrate 111 to the second heat dissipation substrate 112.

Because there are a plurality of connectors 22, there may also be aplurality of fastening screws 331. A quantity of fastening screws 331may be less than a quantity of connectors 22 as long as it is ensuredthat the fastening screws 331 can fasten the connectors 22. In this way,the quantity of the fastening screws 331 can be reduced, and it isavoided that disposing of another component is affected because thefastening screws 331 occupy excessive space.

In an actual disclosure, the fastening screw 331 may be further replacedwith a fastener such as a bolt, and the first through hole and thesecond through hole may be threaded holes or holes without threads.

When at least one of the first through hole and the second through holeis a hole without a thread, the fastener 33 further includes a nut, andthe connector is securely connected to the heat dissipation substrate byusing cooperation between a screw and the nut.

Because the fastening screw 331 used to connect the connector 22 to thesecond heat dissipation substrate 112 implements fastening andconnection by relying on a common threaded connection, a connection isrelatively reliable. In addition, when the connector 22 implements athreaded connection by using the fastening screw 331, the fasteningscrew 331 passes through the through holes on the two different heatdissipation substrates. The first through hole of the connector 22 orthe second through hole on the second heat dissipation substrate 112 isgenerally in point contact with or is in line contact with a thread ofthe fastening screw 331, and a contact surface is relatively small.Therefore, this can further reduce a heat conduction speed of theconnector 22 and the second heat dissipation substrate 112, and ensureheat insulation performance of the first heat dissipation substrate 111and the second heat dissipation substrate 112.

Based on the foregoing implementable manner, the fastener 33 may furtherinclude an elastic member 332, and two ends of the elastic member 332respectively press between the head portion of the fastening screw 331and the first heat dissipation substrate 111, so that the first heatdissipation substrate 111 is in contact with the packaged chip under anelastic force of the elastic member 332. Specifically, the elasticmember 332 may be a conventional elastic element such as a spring, andwhen the elastic member 332 is a spring, the spring may be sleeved onthe fastening screw 331. A fastening manner thereof is relativelysimple.

The elastic member 332 of the fastener 33 can press against both thefastening screw 331 and the first heat dissipation substrate 111. Inaddition, the fastening screw 331 and the second heat dissipationsubstrate 112 are securely connected, and maintain fixed relativepositions. Therefore, under the force of the elastic member 332, thefirst heat dissipation substrate 111 is pressed to the second heatdissipation substrate 112 under the force of the elastic member 332, togenerate a floating effect. This can prevent the first heat dissipationsubstrate 111 from moving far away from the second heat dissipationsubstrate 112, and the first heat dissipation substrate 111 and thesecond heat dissipation substrate 112 can keep being in contact with thepackaged chip as much as possible. To be specific, the heat conductionsurfaces of the first heat dissipation substrate 111 and the second heatdissipation substrate 112 are coplanar.

In an implementable manner of this disclosure, the second heatdissipation substrate 112 is connected to the second end of theconnector 22 by using heat insulation glue. Because the heat insulationglue is in a flowable state before solidifying, the heat insulation gluemay be provided between the second heat dissipation substrate 112 andthe second end of the connector 22 in a manner such as coating, andusage of the heat insulation glue may be freely set based on an actualrequirement. In this way, the heat insulation glue is disposed betweenthe connector 22 and the second heat dissipation substrate 112, toobstruct heat transfer between the connector 22 and the second heatdissipation substrate 112, and further avoid heat transfer between thefirst heat dissipation substrate 111 and the second heat dissipationsubstrate 112. It should be noted that the second heat dissipationsubstrate 112 may alternatively be glued to the second end of theconnector 22 by using another adhesive, to ensure a fastening effect ofthe second heat dissipation substrate 112 and the second end of theconnector 22.

In addition, the second end of the connector 22 may be soldered to thesecond heat dissipation substrate 112 in another fastening manner suchas by using soldering tin, to implement fastening of the second end ofthe connector 22 and the second heat dissipation substrate 112. Becausesoldering tin has relatively high connection strength, soldering tin caneffectively fasten the connector when being used for soldering andconnection.

When the heat sink dissipates heat for the packaged chip, a structure ofthe packaged chip is relatively compact, and different chips have aplurality of possible positions in the packaged chip. Therefore,correspondingly, relative positions and structures of the heatdissipation substrates are also relatively diverse to adapt to heatdissipation requirements of different chips. For example, the secondheat dissipation substrate 112 and the first heat dissipation substrate111 may be provided in parallel with each other and do not interfereeach other. Alternatively, the second heat dissipation substrate 112 maybe provided with a notch, at least a part of the first heat dissipationsubstrate 111 is located in the notch, and an outer-edge shape of thepart of the first heat dissipation substrate 111 that is located in thenotch matches a shape of the notch. Generally, the first heatdissipation substrate 111 may be completely located in the notch of thesecond heat dissipation substrate 112. FIG. 6 is a diagram 1 of relativelocations of a first heat dissipation substrate and a second heatdissipation substrate according to Embodiment 1 of this disclosure. FIG.7 is a diagram 2 of relative locations of a first heat dissipationsubstrate and a second heat dissipation substrate according toEmbodiment 1 of this disclosure. FIG. 8 is a diagram 3 of relativelocations of a first heat dissipation substrate and a second heatdissipation substrate according to Embodiment 1 of this disclosure. Asshown in FIG. 6, FIG. 7, and FIG. 8, the second heat dissipationsubstrate 112 is approximately a rectangular substrate, the edge of thesecond heat dissipation substrate 112 is provided with a notch, and atleast the part of the first heat dissipation substrate 111 or the entirefirst heat dissipation substrate 111 is completely located in the notch.The outer-edge shape of the first heat dissipation substrate 111 matchesthe shape of the notch, and both are rectangles in the figures, so thatthe first heat dissipation substrate 111 and the second heat dissipationsubstrate 112 combine to form a large rectangle.

Because at least the part of the first heat dissipation substrate 111 isinserted into the notch of the second heat dissipation substrate 112,the structure formed by the first heat dissipation substrate 111 and thesecond heat dissipation substrate 112 is relatively compact, and adistance between the first heat dissipation substrate 111 and the secondheat dissipation substrate 112 is relatively small. In this way, spacecan be effectively used, and when an area of the surface of the packagedchip is relatively small, the first heat dissipation substrate 111 andthe second heat dissipation substrate 112 can correspondingly be incontact with each chip in the packaged chip accurately.

It should be noted that regardless of a manner in which the first heatdissipation substrate 111 and the second heat dissipation substrate 112are arranged, it needs to be ensured that the heat conduction surfacesof the first heat dissipation substrate 111 and the second heatdissipation substrate 112 are in a same plane, to ensure desirablecontact with the packaged chip, and avoid that heat dissipationefficiency is affected because the heat dissipation substrate is not incontact with a surface of a corresponding chip in the packaged chip.

In an implementable manner of this disclosure, the first heatdissipation substrate 111 and the second heat dissipation substrate 112may alternatively have an included relationship in the same plane. FIG.9 is a diagram 4 of relative locations of a first heat dissipationsub-substrate and a second heat dissipation sub-substrate according toEmbodiment 1 of this disclosure. As shown in FIG. 9, the second heatdissipation substrate 112 may enclose the outer side of the first heatdissipation substrate 111 and form a closed shape. This disposing manneris applied to a case in which positions of some chips in the packagedchip are relatively close to the center.

To conduct heat of the heat dissipation substrate to another place toachieve a better heat dissipation effect, the heat sink is provided withthe heat dissipation fin connected to the heat dissipation substrate.The heat dissipation fin has a relatively large heat dissipation area,and can dissipate, by using an external cooling airflow, heat gatheredon the heat dissipation fin.

During using, if heat dissipation fins of different heat dissipationsubstrates are connected to each other, for example, the heatdissipation fin of the first heat dissipation substrate 111 is connectedto the heat dissipation fin of the second heat dissipation substrate112, and heat gathered on the heat dissipation fin of the second heatdissipation substrate 112 is higher than heat of the heat dissipationfin of the first heat dissipation substrate 111, the heat dissipationfin of the second heat dissipation substrate 112 transfers heat to theheat dissipation fin of the first heat dissipation substrate 111, sothat a temperature of the heat dissipation fin of the first heatdissipation substrate 111 increases, and heat dissipation of the firstheat dissipation substrate 111 for the chip is affected. When atemperature of a chip continuously increases because of insufficientheat dissipation, normal working of the chip and a service life of thechip are affected.

To resolve the foregoing problem, the heat sink includes: a first heatdissipation fin group 141 used to dissipate heat for the first heatdissipation substrate 111 and a second heat dissipation fin group 142used to dissipate heat for the second heat dissipation substrate 112,the first heat dissipation fin group 141 is located on a surface that isof the first heat dissipation substrate 11 and that is opposite to theheat conduction surface, the second heat dissipation fin group 142 islocated on a surface that is of the second heat dissipation substrate112 and that is opposite to the heat conduction surface, a cold air path142 a is formed inside the second heat dissipation fin group 142, thesecond heat dissipation fin group 142 is provided with second heatdissipation fins, the second heat dissipation fin is located on twosides of the cold air path 142 a, and the first heat dissipation fingroup 141 is located on the cold air path 142 a or an extension line ofthe cold air path 142 a.

Based on different relative positions of the first heat dissipationsubstrate 111 and the second heat dissipation substrate 112, the firstheat dissipation fin group 141 may be located on the cold air path 142 ain the second heat dissipation fin group 142 or an extension line at twoends of the cold air path 142 a.

Specifically, each heat dissipation substrate of the heat sink isfurther connected to a heat dissipation fin group for dissipating heatfor the heat dissipation substrate. When the heat dissipation fin groupdissipates heat for the heat dissipation substrate, a cooling airflowmay be blown into the heat dissipation fin group. The cooling airflowmay be generated by an external air deflection structure, or may begenerated by an active heat dissipation device such as a fan. FIG. 10 isa schematic structural diagram 1 of a heat dissipation fin groupaccording to Embodiment 1 of this disclosure. As shown in FIG. 10, anairflow used to dissipate heat is generally blown from the second heatdissipation substrate 112 to the first heat dissipation substrate 111.In this case, the first heat dissipation substrate 111 is locateddownstream on an air channel, and the second heat dissipation substrate112 is located upstream on the air channel, as shown in FIG. 10. Toenable the first heat dissipation fin group 141 to be in contact with acooling airflow, the second heat dissipation fin group 142 is providedwith a cold air path 142 a passing through the entire second heatdissipation fin group 142, so that an external cooling airflow can passthrough the cold air path 142 a and is blown to the first heatdissipation fin group 141. Because both the first heat dissipation fingroup 141 and the second heat dissipation fin group 142 can be incontact with a cooling airflow, heat gathered on the heat dissipationfin groups can all be effectively dissipated, so that the first heatdissipation fin group 141 and the second heat dissipation fin group 142both have relatively high heat dissipation efficiency, to avoid thatheat on the first heat dissipation substrate 111 or the second heatdissipation substrate 112 cannot be dissipated in time and damages thepackaged chip.

It should be noted that a specific shape and a specific structure of asingle heat dissipation fin in each heat dissipation fin group may bothbe freely set, and this is not limited herein.

It should be noted that to achieve a better effect, an arrangementdirection of the heat dissipation fin may be set to be the same as adirection from which cold air is blown in.

FIG. 11 is a schematic structural diagram 2 of a heat dissipation fingroup according to Embodiment 1 of this disclosure. In a possibleimplementation, to improve heat dissipation efficiency of a heatdissipation substrate, a third heat dissipation fin 143 is furtherdisposed in the cold air path 142 a in the second heat dissipation fingroup 142, and a height of the third heat dissipation fin 143 is lessthan a height of the second heat dissipation fin, as shown in FIG. 11.Because the cold air path has the third heat dissipation fin 143 havinga relatively low height, the third heat dissipation fin can assist heatdissipation of the heat dissipation substrate, and heat dissipationefficiency on the second heat dissipation substrate 112 is ensured. Inaddition, because the height of the third heat dissipation fin 143 isrelatively low, it can still be ensured that cooling airflow can passthrough the cold air path 142 a.

FIG. 12 is a schematic structural diagram 3 of a heat dissipation fingroup according to Embodiment 1 of this disclosure. In another possibleimplementation, fourth heat dissipation fins are further disposed in thecold air path 144, and a density of the fourth heat dissipation fins 144is less than a density of the second heat dissipation fins, as shown inFIG. 12. Similar to the third heat dissipation fin 143, the fourth heatdissipation fin 144 in the cold air path 142 a can increase a heatdissipation area of the entire second heat dissipation fin group 142, toassist heat dissipation of the second heat dissipation substrate 112. Inaddition, because a density of the fourth heat dissipation fins 144 isless than a density of the second heat dissipation fins, a relativelylarge notch exists between the fourth heat dissipation fins 144.Therefore, it can still be ensured that a cooling airflow can passthrough the cold air path 142 a to dissipate heat for the first heatdissipation fin group 141.

When the first heat dissipation substrate 111 and the second heatdissipation substrate 112 have relatively small areas, space foraccommodating the heat dissipation fin groups is limited, and the heatdissipation fin groups may alternatively be stacked when being disposed.FIG. 13 is a schematic structural diagram 4 of a heat dissipation fingroup according to Embodiment 1 of this disclosure. As shown in FIG. 13,the heat sink further includes: a fifth heat dissipation fin group 145used to dissipate heat for the first heat dissipation substrate 111 anda sixth heat dissipation fin group 146 used to dissipate heat for thesecond heat dissipation substrate 112, and the fifth heat dissipationfin group 145 and the sixth heat dissipation fin group 146 are stackedon a surface that is of the heat dissipation substrate and that isopposite to the heat conduction surface.

The fifth heat dissipation fin group 145 may be located between thesixth heat dissipation fin group 146 and the heat dissipation substrate,or the sixth heat dissipation fin group 146 may be located between thefifth heat dissipation fin group 145 and the heat dissipation substrate.In this way, the two heat dissipation fin groups are stacked from top tobottom in a direction perpendicular to the heat conduction surface.Therefore, each heat dissipation fin group may have a relatively largearea, and is distributed on the entire heat dissipation substrate. Aheat dissipation fin group relatively far away from the heat dissipationsubstrate may transfer heat with the heat dissipation substrate in amanner such as by using a heat pipe, to ensure heat dissipation of theheat dissipation substrate. Therefore, the heat dissipation fin groupsrespectively used to dissipate heat for the two heat dissipationsubstrates are stacked on the heat dissipation substrates from top tobottom, so that when an area of the heat dissipation substrate isrelatively small and it is difficult to form an effective cold air path,height space above the heat dissipation substrate can be used to disposethe heat dissipation fin group, to ensure heat dissipation efficiency ofthe heat dissipation substrate.

Based on the foregoing embodiments, to further improve heat dissipationefficiency, a semiconductor cooling chip may be further disposed on theheat conduction surface of the at least one heat dissipation substrate,and the semiconductor cooling chip is in contact with a correspondingchip in the packaged chip. The semiconductor cooling chip is disposed onthe heat conduction surface of the heat dissipation substrate, so that aheat transfer speed of the heat conduction surface may be increased, andheat dissipation efficiency of the heat sink may be improved by using afeature of electron mobility of a semiconductor. Therefore, heatdissipation of each chip in the packaged chip is facilitated, working ofa chip is protected, and a service life of a chip is increased.

In this case, a semiconductor cooling chip may be disposed on heatconduction surfaces of some heat dissipation substrates, or asemiconductor cooling chip may be disposed on heat conduction surfacesof all heat dissipation substrates. A disposing manner and a quantity ofsemiconductor cooling chips may be freely set based on a specific heatdissipation requirement.

In addition, another type of thermoelectric cooler may alternatively beused to replace the semiconductor cooling chip, and a method for usingthe thermoelectric cooler is the same as that in the prior art. Detailsare not described herein again.

In addition, optionally, a heat conduction rate and heat conductionefficiency of the different heat dissipation substrates may be furtherreduced, and a heat insulation effect of the heat dissipation substratesmay be improved by selecting a material of the connector. For example, aheat conduction rate of a material that the connector is made of may beless than a heat conduction rate of a material that the heat dissipationsubstrate is made of.

Specifically, a material such as stainless steel or zinc alloy having alow heat conduction coefficient may generally be selected for theconnector. Compared with a material that the heat dissipation substrateis made of, a heat conduction speed of the selected material isrelatively slow, and heat transfer between the different heatdissipation substrates may be further obstructed, so that a heatdissipation process of each chip is more independent, and it is avoidedthat a chip in the packaged chip that emits more heat interferes normalheat dissipation of a chip that emits less heat.

In this embodiment, the heat sink includes the heat dissipationsubstrate, the connector, and the fastener. The heat dissipationsubstrate is configured to dissipate heat for a packaged chip located onthe circuit board, and the heat dissipation substrate is located on thesurface that is of the packaged chip and that is opposite to the circuitboard; and the heat dissipation substrate includes the first heatdissipation substrate and the second heat dissipation substrate, thefirst heat dissipation substrate and the second heat dissipationsubstrate each have the heat conduction surface that conducts heat witha chip in the packaged chip, different heat conduction surfacescorrespond to different chips, the first end of the connector isfastened to the first heat dissipation substrate, the second end of theconnector suspends on an outer side of the second heat dissipationsubstrate, and the fastener presses against the outer side of the firstheat dissipation substrate, to prevent the first heat dissipationsubstrate from moving far away from the second heat dissipationsubstrate. When temperatures of chips below heat dissipation substratesare different, heat emitted by each chip does not transfer to anotherchip by using the heat dissipation substrate. To be specific, in aprocess of using the heat sink, heat emitted by a chip having a hightemperature does not transfer to a chip having a low temperature,thereby effectively increasing a service life of a chip having arelatively low temperature, and increasing a service life of anelectronic product.

FIG. 14 is a schematic structural diagram of a heat sink according toEmbodiment 2 of this disclosure. In this embodiment, when heat ofdifferent chips in the packaged chip is dissipated, heat transferbetween the different heat dissipation substrates may further beobstructed by using a material having a low heat conduction coefficient.As shown in FIG. 14, the heat sink includes a heat dissipation substrate11. The heat dissipation substrate 11 is configured to dissipate heatfor a packaged chip on a circuit board, and the heat dissipationsubstrate is located on a surface that is of the packaged chip and thatis opposite to the circuit board.

The heat dissipation substrate 11 includes a first heat dissipationsubstrate 111 and a second heat dissipation substrate 112, the firstheat dissipation substrate 111 and the second heat dissipation substrate112 each have a heat conduction surface that conducts heat with a chipin the packaged chip, different heat conduction surfaces correspond todifferent chips, the first heat dissipation substrate 111 is connectedto the second heat dissipation substrate 112 by using a connector 23, aheat conduction coefficient of the connector 23 is less than a heatconduction coefficient of the first heat dissipation sub-substrate 111,and the heat conduction coefficient of the connector 23 is less than aheat conduction coefficient of the second heat dissipation substrate112.

In the heat sink, a plurality of heat dissipation substrates thatdissipate heat for different chips are connected by using the connector23 having a relatively low heat conduction coefficient. Because the heatconduction coefficient of the connector 23 configured to connect twoneighboring heat dissipation substrates is less than that of theconnected heat dissipation substrate, less heat is transferred betweenthe neighboring heat dissipation substrates. When temperatures of chipsbelow each heat dissipation sub-substrate are different, heat emitted byeach chip does not transfer to another chip by using the heatdissipation substrate. To be specific, in a process of using the heatsink, heat emitted by a chip having a high temperature does not transferto a chip having a low temperature, thereby effectively increasing aservice life of the chip having a relatively low temperature, andincreasing a service lives of the packaged chip and an entire electronicproduct.

Specifically, a material such as stainless steel or zinc alloy having alow heat conduction coefficient may be selected for the connector 23.Compared with a material that the heat dissipation substrate is made of,a heat conduction speed of the selected material is relatively slow, andheat transfer between the different heat dissipation substrates may befurther obstructed, so that a heat dissipation process of each chip ismore independent, and it is avoided that a chip in the packaged chipthat emits more heat interferes normal heat dissipation of a chip thatemits less heat.

In an implementable manner of this disclosure, the heat conductionsurfaces of the first heat dissipation substrate 111 and the second heatdissipation substrate 112 are both in a same plane. Because surfacesthat are of chips in the packaged chip and that are away from thecircuit board are all in the same plane, the heat conduction surfaces ofthe first heat dissipation substrate 111 and the second heat dissipationsubstrate 112 are both in the same plane. Therefore, this can ensurethat the heat conduction surfaces of the heat dissipation substrates allare in contact with each chip in the packaged chip, and avoid that theheat dissipation substrates are undesirably in contact with the packagedchip.

In an implementable manner of this disclosure, a material that theconnector 23 is made of is a heat-insulation material. The connector 23is made of the heat-insulation material, and a heat transfer process ofthe neighboring first heat dissipation substrates 111 and second heatdissipation substrate 112 can be alleviated to the maximum extent, sothat an approximate heat insulation state exists between the differentheat dissipation substrates, heat emitted by a chip having a hightemperature is prevented from transferring to a chip having a lowtemperature, and a service life of the chip is increased. A commonheat-insulation material includes plastic, fiberglass, asbestos, or thelike. Because plastic has relatively desirable heat insulationperformance and is formed easily, plastic is a relatively preferablematerial that the connector is made of.

Optionally, to further reduce heat passing through the connector 23, across-sectional area of the connector 23 in a heat transfer direction isgenerally less than a cross-sectional area of a connected part formedwhen the first heat dissipation substrate 111 and the second heatdissipation substrate 112 are directly connected. A first connectionsurface may be defined as a surface that is on the first heatdissipation substrate 111 and that is opposite to the second heatdissipation substrate 112, and a second connection surface may bedefined as a surface that is on the second heat dissipation substrate112 and that is opposite to the first heat dissipation substrate 111.The cross-sectional area of the connector 23 in a heat conductiondirection of the connector 23 should be less than an overlapped area ofthe first connection surface and the second connection surface.Generally, the connector 23 may be of an elongated shape orsheet-shaped, and is joined between the first heat dissipation substrate111 and the second heat dissipation substrate 112. It should be notedthat the shape of the connector 23 is not limited to an elongated shapeor a sheet shape, and may alternatively be another structural formhaving a relatively small cross-sectional area.

In an implementable manner of this disclosure, an arrangement groove1121 is provided at a position that is on the second heat dissipationsubstrate 112 and that corresponds to the connector 23, and thearrangement groove 1121 is used to avoid the connector 23. In this way,because the connector 23 is connected to the second heat dissipationsubstrate 112, to avoid interference between the connector 23 and thesecond heat dissipation substrate 112 and further stably fasten theconnector 23, the second heat dissipation substrate 112 is provided withthe arrangement groove 1121. A size and a depth of the arrangementgroove 1121 both match the connector 23, so that the connector 23 can beplaced in the arrangement groove 1121 to avoid interference between theconnector 23 and the second heat dissipation substrate 112. In addition,a shape of the arrangement groove 1121 can fasten and position theconnector 23 in a direction parallel to the heat dissipation substrate.

In an implementable manner of this disclosure, there are at least twoconnectors 23. When there are a plurality of connectors 23, theplurality of connectors may be symmetrically disposed on two sides ofthe first heat dissipation substrate 111, to strengthen stability ofconnection between the first heat dissipation substrate 111 and thesecond heat dissipation substrate 112.

Optionally, the connector 23 may be directly soldered to the second heatdissipation substrate 112 by using soldering tin, to implement fasteningof the connector and the second heat dissipation substrate.Specifically, when the soldering tin is used for soldering, a materialof the connector 23 usually may be a metal material such as stainlesssteel or zinc alloy that can combine with the soldering tin. Inaddition, the connector 23 may alternatively be glued to the second heatdissipation substrate 112 by using an adhesive, to implement fasteningof the connector 23 and the second heat dissipation substrate 112.

When the connector 23 is connected to the second heat dissipationsubstrate 112 by using soldering tin or an adhesive, the entire heatsink is not detached easily. To implement detachable design of the heatsink, in another implementable manner, the connector 23 may be securelyconnected to the second heat dissipation substrate 112 by using astructure such as a fastening screw. FIG. 15 is another schematicstructural diagram of a heat sink according to Embodiment 2 of thisdisclosure. As shown in FIG. 15, the connector 23 is provided with afirst through hole, and a second through hole is provided at a positionthat is on the second heat dissipation substrate 112 and thatcorresponds to the first through hole. In this case, the heat sinkfurther includes a fastening screw 331, the fastening screw 331 passesthrough the first through hole and the second through hole, the firstheat dissipation substrate 111 is located between a head portion of thefastening screw 331 and the second heat dissipation substrate 112, and atail portion of the fastening screw 331 is securely connected to thesecond heat dissipation substrate 112, to connect the first heatdissipation substrate 111 to the second heat dissipation substrate 112.

Because the fastening screw 331 used to connect the connector 23 to thesecond heat dissipation substrate 112 implements fastening andconnection by relying on a common threaded connection, a connection isrelatively reliable. In addition, in a threaded connection, a throughhole of the connector 23 or the second heat dissipation substrate 112 isgenerally in point contact with or is in line contact with a thread ofthe fastening screw 331, and a contact surface is relatively small.Therefore, this can further reduce a heat conduction speed of theconnector 23 and the second heat dissipation substrate 112, and ensureheat insulation performance of the first heat dissipation substrate 111and the second heat dissipation substrate 112.

Further, based on the foregoing embodiment, the heat sink furtherincludes an elastic member 332, and two ends of the elastic member 332respectively press between the head portion of the fastening screw 331and the first heat dissipation substrate 111, so that the first heatdissipation substrate 111 is in contact with the packaged chip under anelastic force of the elastic member 332.

Because the elastic member 332 can press against both the fasteningscrew 331 and the first heat dissipation substrate 111, and thefastening screw 331 and the second heat dissipation substrate 112 aresecurely connected, and maintain fixed relative positions, under theforce of the elastic member 332, the first heat dissipation substrate111 is pressed to the second heat dissipation substrate 112 under theforce of the elastic member 332, to generate a floating effect. This canprevent the first heat dissipation substrate 111 from moving far awayfrom the second heat dissipation substrate 112, and the first heatdissipation substrate 111 and the second heat dissipation substrate 112can keep being in contact with the packaged chip as much as possible. Tobe specific, the heat conduction surfaces of the first heat dissipationsubstrate 111 and the second heat dissipation substrate 112 arecoplanar.

In an implementable manner of this disclosure, the second heatdissipation substrate 112 is connected to the connector 23 by using heatinsulation glue. The heat insulation glue is disposed between theconnector 23 and the second heat dissipation substrate 112, to obstructheat transfer between the connector 23 and the second heat dissipationsubstrate 112, and further avoid heat transfer between the first heatdissipation substrate 111 and the second heat dissipation substrate 112.

In addition, in this embodiment, a relationship of relative positions ofthe second heat dissipation substrate 112 and the first heat dissipationsubstrate 111 is similar to that in Embodiment 1. In an implementablemanner of this disclosure, the second heat dissipation substrate 112 isprovided with a notch. At least a part of the first heat dissipationsubstrate 111 is located in the notch, and an outer-edge shape of thepart of the first heat dissipation substrate 111 that is located in thenotch matches a shape of the notch, as shown in FIG. 6, FIG. 7, and FIG.8.

In an implementable manner of this disclosure, the first heatdissipation substrate 111 is completely located in the notch.

In an implementable manner of this disclosure, the second heatdissipation substrate 112 encloses the outer side of the first heatdissipation substrate 111 and forms a closed shape, as shown in FIG. 9.

In an implementable manner of this disclosure, the heat sink furtherincludes: a first heat dissipation fin group 141 used to dissipate heatfor the first heat dissipation substrate 111 and a second heatdissipation fin group 142 used to dissipate heat for the second heatdissipation substrate 112, the first heat dissipation fin group 141 islocated on a surface that is of the first heat dissipation substrate 111and that is opposite to the heat conduction surface, the second heatdissipation fin group 142 is located on a surface that is of the secondheat dissipation substrate 112 and that is opposite to the heatconduction surface, a cold air path 142 a is formed inside the secondheat dissipation fin group 142, the second heat dissipation fin group142 is provided with second heat dissipation fins, the second heatdissipation fin is located on two sides of the cold air path 142 a, andthe first heat dissipation fin group 141 is located on the cold air path142 a or an extension line of the cold air path 142 a, as shown in FIG.10.

Optionally, a third heat dissipation fin 143 is further disposed in thecold air path 142 a, and a height of the third heat dissipation fin 143is less than a height of the second heat dissipation fin, as shown inFIG. 11.

Optionally, a fourth heat dissipation fin 144 is further disposed in thecold air path 142 a, and a density of the fourth heat dissipation fins144 is less than a density of the second heat dissipation fins, as shownin FIG. 12.

Optionally, the heat sink further includes: a fifth heat dissipation fingroup 145 used to dissipate heat for the first heat dissipationsubstrate 111 and a sixth heat dissipation fin group 146 used todissipate heat for the second heat dissipation substrate 112, and thefifth heat dissipation fin group 145 and the sixth heat dissipation fingroup 146 are stacked on a surface that is of the heat dissipationsubstrate and that is opposite to the heat conduction surface.

The fifth heat dissipation fin group 145 is located between the sixthheat dissipation fin group 146 and the heat dissipation substrate, orthe sixth heat dissipation fin group 146 is located between the fifthheat dissipation fin group 145 and the heat dissipation substrate, asspecifically shown in FIG. 13.

Optionally, a semiconductor cooling chip is disposed on the heatconduction surface of the at least one heat dissipation substrate, andthe semiconductor cooling chip is in contact with a corresponding chipin the packaged chip.

In this embodiment, the heat sink includes the heat dissipationsubstrate. The heat dissipation substrate is configured to dissipateheat for a packaged chip located on the circuit board, and the heatdissipation substrate is located on the surface that is of the packagedchip and that is opposite to the circuit board; and the heat dissipationsubstrate includes the first heat dissipation substrate and the secondheat dissipation substrate, the first heat dissipation substrate and thesecond heat dissipation substrate each have the heat conduction surfacethat conducts heat with a chip in the packaged chip, different heatconduction surfaces correspond to different chips, the first heatdissipation substrate is connected to the second heat dissipationsubstrate by using the connector, the heat conduction coefficient of theconnector is less than the heat conduction coefficient of the first heatdissipation sub-substrate, and the heat conduction coefficient of theconnector is less than the heat conduction coefficient of the secondheat dissipation substrate. In this way, because neighboring heatdissipation substrates are connected by using the connector having arelatively low heat conduction coefficient, when temperatures of chipsbelow heat dissipation substrates are different, heat emitted by eachchip does not transfer to another chip by using the heat dissipationsubstrate. To be specific, in a process of using the heat sink, heatemitted by a chip having a high temperature does not transfer to a chiphaving a low temperature, thereby effectively increasing a service lifeof a chip having a relatively low temperature, and increasing a servicelife of an electronic product.

FIG. 16 is a schematic structural diagram of a heat sink according toEmbodiment 3 of this disclosure. An overall structure of the heat sinkin this embodiment is similar to that in Embodiment 1. Details are notdescribed herein again. A difference lies in that the fastening screw isnot selected as the fastener configured to fasten the connector and thesecond heat dissipation substrate, and instead a double-layer studstructure is used. Specifically, as shown in FIG. 16, the fastener 33includes: a first positioning stud 333 a and a second positioning stud333 b; and a bottom end of the first positioning stud 333 a is connectedto the second heat dissipation substrate 112, an axial direction of thefirst positioning stud 333 a is perpendicular to a plane in which thesecond heat dissipation substrate 112 lies, the second positioning stud333 b can be screwed into a top end of the first positioning stud 333 a,and the second end of the connector 22 is fastened at a screwed positionof the first positioning stud 333 a and the second positioning stud 333b.

A double-layer stud structure is used, the second end of the connector22 is fastened between the first positioning stud 333 a and the secondpositioning stud 333 b, and the first positioning stud 333 a is fastenedon the second heat dissipation substrate 112. In this way, a connectionbetween the connector 22 and the second heat dissipation substrate 112is indirectly implemented by using the stud. A contact surface of theconnector 22 and the positioning stud is generally relatively small, andthere is usually a gap. Therefore, a heat transfer speed and heattransfer efficiency of the connector 22 and the positioning stud areboth relatively low, and heat transfer to different heat dissipationsubstrates through the connector can be relatively desirably avoided.

In an implementable manner of this disclosure, a perpendicular distancebetween the second end of the connector 22 and the plane in which thesecond heat dissipation substrate 112 lies is different from aperpendicular distance between the first end of the connector 22 and theplane in which the second heat dissipation substrate 112 lies.

Specifically, because the connector 22 may be connected to the secondheat dissipation substrate 112 by using a structure such as adouble-layer positioning stud, to avoid another connection structure,the second end and the first end of the connector 22 may generallylocated at positions away from the plane in which the second heatdissipation substrate 112 lies by different distances, so that thesecond end of the connector 22 avoids the connection structure forfastening.

Because heights of the second end and the first end of the connector 22are different, the first end of the connector 22 may be connected to thesecond end of the connector 22 by using a bending segment. In addition,the connector 22 may alternatively be a structure such as an arc thatmay satisfy a requirement that two ends have a height difference.Details are not described herein again.

In this embodiment, the heat sink includes the heat dissipationsubstrate, the connector, and the fastener. The heat dissipationsubstrate is configured to dissipate heat for a packaged chip located onthe circuit board, and the heat dissipation substrate is located on thesurface that is of the packaged chip and that is opposite to the circuitboard; and the heat dissipation substrate includes the first heatdissipation substrate and the second heat dissipation substrate, thefirst heat dissipation substrate and the second heat dissipationsubstrate each have a heat conduction surface that conducts heat with achip in the packaged chip, different heat conduction surfaces correspondto different chips, the first end of the connector is fastened to thefirst heat dissipation substrate, the second end of the connectorsuspends on an outer side of the second heat dissipation substrate, andthe fastener presses against an outer side of the first heat dissipationsubstrate, to prevent the first heat dissipation substrate from movingfar away from the second heat dissipation substrate. The fastenerincludes: a first positioning stud and a second positioning stud; and abottom end of the first positioning stud is connected to the second heatdissipation substrate, an axial direction of the first positioning studis perpendicular to a plane in which the second heat dissipationsubstrate lies, the second positioning stud can be screwed into a topend of the first positioning stud, and the second end of the connectoris fastened at a position at which the first positioning stud is screwedinto the second positioning stud. When temperatures of chips below heatdissipation substrates are different, heat emitted by each chip does nottransfer to another chip by using the heat dissipation substrate. To bespecific, in a process of using the heat sink, heat emitted by a chiphaving a high temperature does not transfer to a chip having a lowtemperature, thereby effectively increasing a service life of a chiphaving a relatively low temperature, and increasing a service life of anelectronic product.

FIG. 17 is a schematic structural diagram of a heat sink according toEmbodiment 4 of this disclosure. An overall structure and a workingprinciple of the heat sink in this embodiment are similar to that inEmbodiment 2. Details are not described herein again. A difference liesin that when the connector is detachably connected to the second heatdissipation substrate, a double-layer stud structure similar to that inEmbodiment 3 is used. Specifically, as shown in FIG. 17, the heat sinkincludes: a first positioning stud 333 a and a second positioning stud333 b. A bottom end of the first positioning stud 333 a is connected tothe second heat dissipation substrate 112, an axial direction of thefirst positioning stud 333 a is perpendicular to a plane in which thesecond heat dissipation substrate 112 lies, the second positioning stud333 b can be screwed into a top end of the first positioning stud 333 a,the first end of the connector 23 is fastened to the first heatdissipation substrate 111, and the second end of the connector 23 isfastened at a screwed position of the first positioning stud 333 a andthe second positioning stud 333 b.

In an implementable manner of this disclosure, a perpendicular distancebetween the second end of the connector 23 and the plane in which thesecond heat dissipation substrate 112 lies is different from aperpendicular distance between the first end of the connector 23 and theplane in which the second heat dissipation substrate 112 lies.

Because the connector 23 may be connected to the second heat dissipationsubstrate 112 by using a structure such as a double-layer positioningstud, to avoid another connection structure, the second end and thefirst end of the connector 23 may generally located at positions awayfrom the plane in which the second heat dissipation substrate 112 liesby different distances, so that the second end of the connector 23avoids the connection structure for fastening.

In an implementable manner of this disclosure, the first end of theconnector 23 is connected to the second end of the connector 23 by usinga bending segment. In addition, the connector 23 may alternatively be astructure such as an arc that may satisfy a requirement that two endshave a height difference. Details are not described herein again.

In this embodiment, the heat sink includes the heat dissipationsubstrate. The heat dissipation substrate is configured to dissipateheat for a packaged chip located on a circuit board, and the heatdissipation substrate is located on a surface that is of the packagedchip and that is opposite to the circuit board; and the heat dissipationsubstrate includes a first heat dissipation substrate and a second heatdissipation substrate, the first heat dissipation substrate and thesecond heat dissipation substrate each have a heat conduction surfacethat conducts heat with a chip in the packaged chip, different heatconduction surfaces correspond to different chips, the first heatdissipation substrate is connected to the second heat dissipationsubstrate by using a connector, a heat conduction coefficient of theconnector is less than a heat conduction coefficient of the first heatdissipation sub-substrate, and the heat conduction coefficient of theconnector is less than a heat conduction coefficient of the second heatdissipation substrate. The fastener includes: a first positioning studand a second positioning stud; and a bottom end of the first positioningstud is connected to the second heat dissipation substrate, an axialdirection of the first positioning stud is perpendicular to a plane inwhich the second heat dissipation substrate lies, the second positioningstud can be screwed into a top end of the first positioning stud, andthe second end of the connector is fastened at a position at which thefirst positioning stud is screwed into the second positioning stud. Inthis way, because neighboring heat dissipation substrates are connectedby using the connector having a relatively low heat conductioncoefficient, when temperatures of chips below heat dissipationsubstrates are different, heat emitted by each chip does not transfer toanother chip by using the heat dissipation substrate. To be specific, ina process of using the heat sink, heat emitted by a chip having a hightemperature does not transfer to a chip having a low temperature,thereby effectively increasing a service life of a chip having arelatively low temperature, and increasing a service life of anelectronic product.

In addition, an embodiment of this disclosure further provides a heatdissipation apparatus, including at least two heat sinks according toany one of Embodiment 1 or Embodiment 4 and at least one heat pipe,where

each heat sink corresponds to a packaged chip; and

two ends of the heat pipe are respectively connected to heat dissipationsubstrates of different heat sinks, to transfer heat of a heat sinkcorresponding to a packaged chip in a heat emitting state to a heat sinkcorresponding to a packaged chip that does not emit heat.

FIG. 18 is a specific schematic structural diagram of a heat dissipationapparatus according to Embodiment 5 of this disclosure. As shown in FIG.18, the heat dissipation apparatus provided in this embodiment isconfigured to dissipate heat for a first packaged chip 21 and a secondpackaged chip 22. The heat dissipation apparatus provided in thisembodiment specifically includes: a first heat sink 23, a second heatsink 24, and a heat pipe 25. The first heat sink 23 is located above thefirst packaged chip 21, and is configured to dissipate heat for thefirst packaged chip 21. The second heat sink 24 is located above thesecond packaged chip 22, and is configured to dissipate heat for thesecond packaged chip 22. The heat pipe 25 is connected between the firstheat sink 23 and the second heat sink 24. The first heat sink 23includes a heat dissipation substrate 231 and a heat dissipation fin 232provided on the heat dissipation substrate 231; and the second heat sink24 includes a heat dissipation substrate 241 and a heat dissipation fin242 provided on the heat dissipation substrate 241.

Assuming that the first packaged chip 21 is in a heat emitting state,and the second packaged chip 22 does not emit heat, the heat pipe 25 maytransfer heat of the first heat sink 23 to the second heat sink 24, sothat the second heat sink 24 assists heat dissipation of the firstpackaged chip 22. The second packaged chip 22 is not in a working orheat emitting state, and heat dissipation is not required temporarily.

In this embodiment, the heat dissipation apparatus includes at least twoheat sinks and at least one heat pipe. Each heat sink corresponds to apackaged chip; and two ends of the heat pipe are respectively connectedto heat dissipation substrates of different heat sinks, to transfer heatof a heat sink corresponding to a packaged chip in a heat emitting stateto a heat sink corresponding to a packaged chip that does not emit heat.Heat of a packaged chip that is in a working and heat emitting state istransferred, by using the connection between the heat sink and the heatpipe, to a heat sink corresponding to a packaged chip that does not workor does not emit heat, to more effectively facilitate temperaturereduction of different packaged chips.

An embodiment of this disclosure further provides a heat dissipationsystem. The heat dissipation system includes: at least one heat sinkaccording to any one of the foregoing embodiments and at least onepackaged chip, where each heat sink corresponds to a packaged chip, andthe heat sink is used to dissipate heat for the packaged chip.

FIG. 19 is a specific schematic structural diagram of a heat dissipationsystem according to Embodiment 6 of this disclosure. As shown in FIG.19, the heat dissipation system provided in this embodiment isconfigured to dissipate heat for a first packaged chip 31 and a secondpackaged chip 32. The heat dissipation system provided in thisembodiment specifically includes: the first packaged chip 31, the secondpackaged chip 32, a first heat sink 33, and a second heat sink 34, where

the first heat sink 33 is located above the first packaged chip 31 andis configured to dissipate heat for the first packaged chip 31, and thesecond heat sink 34 is located above the second packaged chip 32 and isconfigured to dissipate heat for the second packaged chip 32.

An implementation principle and a technical effect of the heatdissipation system in this embodiment are similar to that in theforegoing embodiments. Details are not described herein again.

An embodiment of this disclosure further provides a communicationsdevice, including at least one heat sink according to any one ofEmbodiment 1 to Embodiment 4, at least one packaged chip, and at leastone circuit board, where

each circuit board is provided with at least one packaged chip; and

each heat sink corresponds to a packaged chip, and the heat sink is usedto dissipate heat for the packaged chip.

FIG. 20 is a specific schematic structural diagram of a communicationsdevice according to Embodiment 7 of this disclosure. As shown in FIG.20, a communications device 400 provided in this embodiment internallyincludes a circuit board 40. The circuit board 40 is provided with apackaged chip 41, the packaged chip 41 is electrically connected to acircuit on the circuit board 40, and the packaged chip 41 is providedwith a heat sink 42 configured to dissipate heat for the packaged chip41. A structure and an implementation principle of the heat sink 42 areboth similar to that of the heat sink in the foregoing embodiments.Details are not described herein again.

An implementation principle and a technical effect of the heat sink ofthe communications device in this embodiment are similar to that of theheat sink in the foregoing embodiments. Details are not described hereinagain.

1. A heat sink, comprising: a heat dissipation substrate, a connector,and a fastener, wherein: the heat dissipation substrate is configured todissipate heat for a packaged chip located on a circuit board, whereinthe heat dissipation substrate is located on a surface that is of thepackaged chip and that is opposite to the circuit board, and wherein thepackaged chip includes a plurality of chips packaged in one packagebody; and the heat dissipation substrate comprises a first heatdissipation substrate and a second heat dissipation substrate, whereinthe first heat dissipation substrate and the second heat dissipationsubstrate each have a heat conduction surface that conducts heat with achip in the plurality of chips, wherein different heat conductionsurfaces correspond to different chips in the plurality of chips,wherein a first end of the connector is fastened to the first heatdissipation substrate, wherein a second end of the connector suspends onan outer side of the second heat dissipation substrate, wherein thesecond heat dissipation substrate is connected to the second end of theconnector by using heat insulation material and wherein the fastenerpresses against an outer side of the first heat dissipation substrate toprevent the first heat dissipation substrate from moving away from thesecond heat dissipation substrate.
 2. The heat sink according to claim1, wherein the heat conduction surfaces of the first heat dissipationsubstrate and the second heat dissipation substrate are both in a sameplane.
 3. The heat sink according to claim 2, wherein the connector isof an elongated shape.
 4. The heat sink according to claim 2, whereinthe connector is sheet-shaped.
 5. The heat sink according to claim 1,wherein an arrangement groove is provided at a position that is on thesecond heat dissipation substrate and that corresponds to the connector,and wherein the arrangement groove is used to avoid the connector. 6.The heat sink according to claim 1, wherein the connector is providedwith a first through hole, and wherein a second through hole is providedat a position that is on the second heat dissipation substrate and thatcorresponds to the first through hole; and wherein the fastener furthercomprises a fastening screw, wherein the fastening screw passes throughthe first through hole and the second through hole, wherein the firstheat dissipation substrate is located between a head portion of thefastening screw and the second heat dissipation substrate, and wherein atail portion of the fastening screw is securely connected to the secondheat dissipation substrate to connect the first heat dissipationsubstrate to the second heat dissipation substrate.
 7. The heat sinkaccording to claim 6, wherein the fastener further comprises an elasticmember, and wherein two ends of the elastic member respectively pressbetween the head portion of the fastening screw and the first heatdissipation substrate, so that the first heat dissipation substrate isin contact with the packaged chip under an elastic force of the elasticmember.
 8. The heat sink according to claim 1, wherein the heatinsulation material is heat insulation glue.
 9. The heat sink accordingto claim 1, wherein the fastener comprises: a first positioning stud;and a second positioning stud, wherein a bottom end of the firstpositioning stud is connected to the second heat dissipation substrate,wherein an axial direction of the first positioning stud isperpendicular to a plane in which the second heat dissipation substratelies, wherein the second positioning stud can be screwed into a top endof the first positioning stud, and wherein the second end of theconnector is fastened at a position at which the first positioning studis screwed into the second positioning stud.
 10. The heat sink accordingto claim 9, wherein a perpendicular distance between the second end ofthe connector and the plane in which the second heat dissipationsubstrate lies is different from a perpendicular distance between thefirst end of the connector and the plane in which the second heatdissipation substrate lies.
 11. The heat sink according to claim 10,wherein the first end of the connector is connected to the second end ofthe connector by using a bending segment.
 12. The heat sink according toclaim 1, wherein the second heat dissipation substrate is provided witha notch, wherein at least a part of the first heat dissipation substrateis located in the notch, and wherein an outer-edge shape of the part ofthe first heat dissipation substrate that is located in the notchmatches a shape of the notch.
 13. The heat sink according to claim 12,wherein the first heat dissipation substrate is completely located inthe notch.
 14. The heat sink according to claim 1, wherein the secondheat dissipation substrate encloses the outer side of the first heatdissipation substrate and forms a closed shape.
 15. The heat sinkaccording to claim 1, further comprising: a first heat dissipation fingroup used to dissipate heat for the first heat dissipation substrate;and a second heat dissipation fin group used to dissipate heat for thesecond heat dissipation substrate, wherein the first heat dissipationfin group is located on a surface that is of the first heat dissipationsubstrate and that is opposite to the heat conduction surface, whereinthe second heat dissipation fin group is located on a surface that is ofthe second heat dissipation substrate and that is opposite to the heatconduction surface, wherein a cold air path is formed inside the secondheat dissipation fin group, wherein the second heat dissipation fingroup is provided with second heat dissipation fins, wherein the secondheat dissipation fins are located on two sides of the cold air path, andwherein the first heat dissipation fin group is located in the cold airpath or on an extension line of the cold air path.
 16. The heat sinkaccording to claim 15, wherein third heat dissipation fins are furtherdisposed in the cold air path, and wherein a height of the third heatdissipation fin is less than a height of the second heat dissipationfin.
 17. The heat sink according to claim 15, wherein fourth heatdissipation fins are further disposed in the cold air path, and whereina density of the fourth heat dissipation fins is less than a density ofthe second heat dissipation fins.
 18. The heat sink according to claim1, further comprising: a fifth heat dissipation fin group used todissipate heat for the first heat dissipation substrate; and a sixthheat dissipation fin group used to dissipate heat for the second heatdissipation substrate, wherein the fifth heat dissipation fin group andthe sixth heat dissipation fin group are stacked on a surface that is ofthe heat dissipation substrate and that is opposite to the heatconduction surface; and wherein: the fifth heat dissipation fin group islocated between the sixth heat dissipation fin group and the heatdissipation substrate, or the sixth heat dissipation fin group islocated between the fifth heat dissipation fin group and the heatdissipation substrate.
 19. The heat sink according to claim 1, wherein aheat conduction rate of a material that the connector is made of is lessthan a heat conduction rate of a material that the heat dissipationsubstrate is made of.
 20. A heat dissipation system, comprising: atleast one heat sink; and at least one packaged chip, wherein each heatsink corresponds to a packaged chip and is used to dissipate heat forthe packaged chip, and wherein each heat sink comprises: a heatdissipation substrate, a connector, and a fastener, wherein: the heatdissipation substrate is configured to dissipate heat for a packagedchip located on a circuit board, wherein the packaged chip includes aplurality of chips packaged in one package body, and wherein the heatdissipation substrate is located on a surface that is of the packagedchip and that is opposite to the circuit board; and the heat dissipationsubstrate comprises a first heat dissipation substrate and a second heatdissipation substrate, wherein the first heat dissipation substrate andthe second heat dissipation substrate each have a heat conductionsurface that conducts heat with a chip in the plurality of chips,wherein different heat conduction surfaces correspond to different chipsin the plurality of chips, wherein a first end of the connector isfastened to the first heat dissipation substrate, wherein a second endof the connector suspends on an outer side of the second heatdissipation substrate, wherein the second heat dissipation substrate isconnected to the second end of the connector by using heat insulationmaterial and wherein the fastener presses against an outer side of thefirst heat dissipation substrate to prevent the first heat dissipationsubstrate from moving away from the second heat dissipation substrate.21. A communications device, comprising: at least one heat sink; atleast one packaged chip; and at least one circuit board, wherein: eachcircuit board is provided with at least one packaged chip; each heatsink corresponds to a packaged chip and is used to dissipate heat forthe packaged chip; and each heat sink comprises: a heat dissipationsubstrate, a connector, and a fastener, wherein: the heat dissipationsubstrate is configured to dissipate heat for a packaged chip located ona circuit board, wherein the packaged chip includes a plurality of chipspackaged in one package body, and wherein the heat dissipation substrateis located on a surface that is of the packaged chip and that isopposite to the circuit board; and the heat dissipation substratecomprises a first heat dissipation substrate and a second heatdissipation substrate, wherein the first heat dissipation substrate andthe second heat dissipation substrate each have a heat conductionsurface that conducts heat with a chip in the plurality of chips,wherein different heat conduction surfaces correspond to different chipsin the plurality of chips, wherein a first end of the connector isfastened to the first heat dissipation substrate, wherein a second endof the connector suspends on an outer side of the second heatdissipation substrate, wherein the second heat dissipation substrate isconnected to the second end of the connector by using heat insulationmaterial and wherein the fastener presses against an outer side of thefirst heat dissipation substrate to prevent the first heat dissipationsubstrate from moving away from the second heat dissipation substrate.